The technology generally relates to mechanical keyboards for use with touchscreen computing devices such as tablet computers, smart phones and the like. Mechanical keyboards comprise a plurality of individual keypads arranged in rows in a frame or chassis. The keypads are biased into a rest position by a biasing mechanism such as a spring or other biasing mechanism and are depressible by a user during typing. One or more sensors in the mechanical keyboard detect depression of individual ones of the keypads and in this way a user is able to depress keypads of the mechanical keyboard in order to generate a signal from the sensors where the signal specifies characters relating to the keypads. Mechanical keyboards are typically powered by a power source such as from a battery or a wired connection to a host computer.
In contrast, software keyboards comprise graphical elements that represent keypads displayed on a touchscreen display, and do not have depressible keypads. In the case of a software keyboard the touchscreen display enters a keyboard mode when the graphical elements depicting the keypads are displayed. In the keyboard mode, touch events at the touchscreen display are interpreted as selections of one or more of the keypads in order to type characters for input to a computing device associated with the touchscreen display.
For typing text into touchscreen devices, software keyboards are typically used since these are simple to display on a touchscreen and are intuitive to operate. Software keyboards are convenient for an end user since only the touchscreen device needs to be stored or transported and there is no need to store or transport a mechanical keyboard. However, software keyboards are difficult to use for touch typing as compared with mechanical keyboards due to a variety of reasons. Often the software keyboard does not feel very realistic to an end user (where realistic is like a mechanical keyboard) and this makes it harder to use the software keyboard. Often the user is unable to rest his or her hands easily in a home position ready for touch typing since the flat surface of the touchscreen device is cold and hard to the touch. The user may try to lift his or her wrists away from or over the edge of the touchscreen in order that the wrists do not interfere with the software keyboard. Over time the user has an increased risk of developing repetitive strain injuries due to in appropriate posture during typing using the software keyboard.
Manufacturing costs for software keyboards are significantly lower than for mechanical keyboards and in general, there is a desire to reduce manufacturing costs for mechanical keyboards. When mechanical keyboards are to be transported such as for use with portable computing devices there is a desire to improve the robustness and reduce the weight of the mechanical keyboards.
The embodiments described below are not limited to implementations which solve any or all of the disadvantages of known mechanical keyboards.